make sure we fetch source flags when expiring while pulling new

otherwise important messages may be incorrectly aborted.

src/run-tests.pl

@@ -1251,20 +1251,21 @@ my @x35 = (
   A, "*F", "*F", "*F",
   B, "*", "*", "*",
   C, "*", "", "",
-  D, "*", "", "",
+  D, "*F", "", "",
   E, "*", "", "",
   F, "*", "", "",
   G, "*", "", "",
-  H, "*", "", "",
+  H, "*F", "", "",
 );
 
 my @O35 = ("", "", "Sync New\nMaxMessages 3\nExpireUnread yes\n");
 my @X35 = (
   H, E, H,
   B, "", "+~", "+T",
+  D, "", "*F", "*F",
   F, "", "*", "*",
   G, "", "*", "*",
-  H, "", "*", "*",
+  H, "", "*F", "*F",
 );
 test("max messages + expire - too many new", \@x35, \@X35, \@O35);
 

src/sync.c

@@ -792,6 +792,8 @@ box_opened2( sync_vars_t *svars, int t )
 		svars->any_expiring = 1;
 	if (svars->any_expiring) {
 		opts[N] |= OPEN_OLD | OPEN_FLAGS;
+		if (chan->ops[N] & (OP_NEW | OP_RENEW))
+			opts[F] |= OPEN_FLAGS;
 	}
 	svars->opts[F] = svars->drv[F]->prepare_load_box( ctx[F], opts[F] );
 	svars->opts[N] = svars->drv[N]->prepare_load_box( ctx[N], opts[N] );